Sofa



FIG. 1 is a perspective view of the sofa.

FIG. 2 is a front elevational view of the sofa.

FIG. 3 is a rear elevational view of the sofa.

FIG. 4 is a left side view of the sofa.

FIG. 5 is a right side view of the sofa.

FIG. 6 is a top view of the sofa; and,

FIG. 7 is a bottom view of the sofa.

The broken lines in FIGS. 1-5 and 7 form no part of the claimed design.

The ornamental design for a sofa, as shown and described.